DE 10 2010 022 908 A1 relates to a battery with temperature detection and use of such a battery. The battery comprises a plurality of electrical flat cells which are connected to one another in parallel and/or in series. Said flat cells are arranged in rows one next to the other transversely with respect to their flat sides and form an essentially prismatic arrangement. In order to acquire more precise information about the state of the individual flat cells during the operation of the battery, and to be able to use said information, for example, for adapted temperature management, in each case a thermally connected heat dissipation plate, in which in each case at least one temperature sensor is integrated, is provided in the arrangement on at least one flat side of a plurality of the flat cells.
The heat dissipation plates can be fabricated, for example, from two parts, wherein depressions for accommodating the temperature sensors and the connecting line are provided in one part. The two parts of the heat dissipation plate are connected to one another via attachment means such as, for example, latching pins and corresponding latching openings. The heat dissipation plates can also be used to mechanically secure the battery cells, wherein the battery cell is connected to the plate, for example, by a screwed connection and/or a thermally conductive bonding. In a further embodiment there is provision for the heat dissipation plates to be connected to a cooling block. An air gap or a coolant passage can be provided between two battery cells.
US 2005/02106221 A1 discloses a method for manufacturing lithium polymer batteries with a high capacitance and a cooling system which is connected thereto. The cooling system comprises a multiplicity of pipes which run between the individual battery cells. The individual battery cells are assigned temperature sensors. The temperature sensors control a fan which drives an airflow through the pipes in order to cool the battery cells according to requirements.
DE 10 2010 055 612 A1 discloses a device for sensing the temperature of individual battery cells. The device serves to sense the temperature of individual battery cells which are connected to form a battery by means of current deflectors and/or bus bars. The device has temperature sensors which are arranged in the region of the individual battery cells. Furthermore, said device has a voltage-measuring means for each of the individual battery cells, which voltage-measuring means is in contact with, in each case, one of the electrodes of each of the individual battery cells via, in each case, one electrical contact. A temperature sensor is arranged on each of the electrical contacts.
Contemporary battery systems for electric vehicles and hybrid vehicles comprise prismatic, cylindrical or pouch secondary cells. The types of battery cell which are used for the most part nowadays generally have a connection to their housing or to their sleeve which leads the negative anode and the positive cathode of the secondary cell from the interior of the battery cell outside. Prismatic lithium secondary cells usually contain what are referred to as windings (jelly rolls) in which the anode, separator and cathode are introduced in a layered fashion and in a wound state into the housing of the battery cell. Contact is made metallically with the windings in the interior of the cells and, as already mentioned above, connections thereto lead out of the housing of the battery cell via connecting poles.
A plurality of battery cells can be connected in parallel in order to implement higher power or a higher energy content. This is done, for example, by using cell connectors with which a plurality of battery cells are connected electrically in parallel. The cell connectors are ultimately used to connect in serial fashion to one another the battery cells or groups of battery cells which are connected in parallel, in order to make available a sufficiently high voltage or a sufficiently high electrical power for the respective use.
A plurality of battery cells are generally combined to form one battery module. In a general case, the battery module comprises a module controller (CSC). The module controller (CSC) measures battery cell voltages and battery cell temperatures. A plurality of battery modules are in turn connected to one another to form a battery pack. This battery pack contains a battery control unit (BCU) which evaluates the data of the module controllers (CSC) and constitutes the communication interface with the vehicle.
Furthermore, relays, fuses, a cooling system, a degassing system, a low-voltage interface, various current-measuring entities and safety circuits are usually contained in the battery pack.
It is highly significant to sense as precisely as possible the temperatures which occur in the battery cells, since they constitute, together with the current and voltage, the most important safety-relevant measurement variables on the basis of which a battery management system regulates a battery pack and communicates with the vehicle. In the solutions which are known previously from the prior art, temperature sensors are generally attached to the cell connectors. This entails the disadvantage that the cell connectors, and also the cell terminals of the battery cells, can have a thermal capacity and a thermal resistance which is not negligible in certain cases, with the result that the temperature which is measured at the cell connector by the temperature sensors is a very imprecise representation of the actual temperature of the battery cell, a temperature profile can be represented only with a delay, and a considerably lower amplitude can result.
Applying temperature-measuring points directly to the housings of the battery cells constitutes a challenge in terms of production technology, and in addition the durability is significantly lower than in the case of a connection of the temperature sensors to the cell connector. This connection can be implemented, for example, by means of ultrasonic welding, but this is not possible on the housing of the battery cell which usually has a surface coating.